Field of Invention
This invention pertains to valves used in to restrict the flow of liquid in a line. More particularly, this invention is a flush valve comprising a plug valve, a first cleanout and a second cleanout to be used when flushing a Heating Ventilation and Air Conditioning (HVAC) line.
Prior Art
spring loaded plug valves are often designed to seal off the flow between two sections of pipe. These spring loaded plug valves can be operated by hand or a pressurized fluid and the spring loaded plug valves provide for a positive seat that prevents any leakage. Unlike the present invention, these spring loaded plug valves may be left in the closed position when used in the drain lines of an HVAC system. When these spring loaded plug valves are left is a closed position, water can backup in the HVAC drain line and eventually flood a structure in which the HVAC system is installed. Additionally, cleanouts are not provided to flush an HVAC system.
The Flush Valve of the present invention has a plug assembly that immediately opens a plug valve when sufficient pressure to keep the plug valve in a closed is removed. This prevents the present invention from being left is a closed state once drain lines are flushed, resulting in water from the HVAC system backing up and flooding a structure. Additionally, a middle leg of a standard pipe fitting, such as a tee pipe fitting, can be drilled out and the plug assembly inserted, transforming the standard pipe fitting into a new plug valve. A first and a second cleanout each can be made by using the tee pipe fitting with a cap installed on the middle leg of the fitting. The new plug valve is positioned between the first cleanout and the second cleanout to form the Flush Valve.
Valves used in conventional HVAC systems have an objective to control a flow of a liquid or a gas. In such conventional systems, some leakage of the liquid or gas can usually be tolerated. The present invention is intended for use on heating, ventilation, and air conditioning drain systems to allow the systems to be flushed. A small amount of leakage can be tolerated and a positive sealing action preventing all flow is not required of the present invention when the valve is closed. The present invention is a Flush Valve comprising a plug valve located between a first cleanout and a second cleanout. The Flush Valve is designed to be placed in a drain line of and HVAC system. This will allow a first section of the drain line between the HVAC system and the valve, and a second section of the drain line located between valve and an exit of the drain line to purge each section of the drain line.
The present invention is a plug valve having a plug assembly inserted in a middle opening of a middle portion of a pipe fitting. The plug valve is closed by applying a force to a plug stem connected to a plug so that the force moves the plug against an interior surface of a base portion, such as a base interior wall of the pipe fitting, closing off flow in the base portion between a first opening and a second opening. The first cleanout may be connected to the first opening and the second cleanout may be connected to the second opening of the plug valve. To open the plug valve, the force on the plug stem is removed, and a spring decompresses causing the plug to move away from the base interior wall of the base portion, opening up the flow between the first opening and the second opening of the base portion of the pipe fitting. With the flush valve closed, the first cleanout can be opened and a pressure or a suction force applied to the opened first cleanout to dislodge any debris in the drain line between the HVAC system and the plug valve. The second cleanout can be opened and the pressure or suction applied to the second opened cleanout to dislodge any debris in the drain line between the plug valve and the exit of the drain line.